Detected PDF document which is malformed and might be used to exploit the PDF reader security vulnerability
. Of course the file may be simply corrupted for any other reasons, hence assigned "Suspicious" Severity
— Detected security weakness exploit or known malicious content. The file is dangerous. Technically, all of the detections having this Severity
level are imposing the highest threat to the user. Thus the websites containing such files should be avoided. (e.g. detected PDF with embedded known malware. Implications — if user opens it in Adobe Reader or the file automatically opens in the browser reader plugin, then the targeted device will be attacked.)
As a general safety rule, all files in the range of S2-S4 should alert your attention. If you don't trust the website that hosts these files you should think again before visiting it.